Using a large sample of exogenous events that negatively affected Korean banks during the 1997-1998 period, we examine the value of durable bank relationships in Korea. We show that adverse shocks to banks have a negative effect not only on the value of the banks themselves, but also on the value of their client firms, and that this adverse effect on firm value is a decreasing function of the financial health of both banks and client firms. Our results are concentrated in the second half of the sample period, when banks experienced severe difficulties.